The Astrophysical Journal Letters最新文献_第6页

Quantifying the Distribution of Europium in the Milky Way Disk: Its Connection to Planetary Habitability and the Source of the r-process 银河系盘中铕的定量分布：与行星可居住性的关系及r-过程的来源

The Astrophysical Journal Letters Pub Date : 2025-09-23 DOI: 10.3847/2041-8213/adfb4d

Evan M. Carrasco, Matthew Shetrone, Francis Nimmo, Enrico Ramirez-Ruiz, Joel Primack, Natalie M. Batalha and Brady Lobmeyer

{"title":"Quantifying the Distribution of Europium in the Milky Way Disk: Its Connection to Planetary Habitability and the Source of the r-process","authors":"Evan M. Carrasco, Matthew Shetrone, Francis Nimmo, Enrico Ramirez-Ruiz, Joel Primack, Natalie M. Batalha and Brady Lobmeyer","doi":"10.3847/2041-8213/adfb4d","DOIUrl":"https://doi.org/10.3847/2041-8213/adfb4d","url":null,"abstract":"The astrophysical site of the r-process remains one of the most pressing questions in stellar nuclear synthesis. Although multiple theoretical sites have been proposed, with some observational counterparts available, the current Galactic distribution cannot be reproduced from a single consistent injection site. To disentangle the prospective sites of r-process production, the distribution of r-process elements in the Galaxy today must be scrutinized. In this study, we find that the intrinsic star-to-star distribution of the r-process element europium (Eu) at a fixed metallicity and temperature has a small intrinsic [Eu/H] scatter of 0.025 dex. In addition to a small dispersion, we demonstrate an anticorrelation between [Eu/α] and [α/H] consistent with r-process production being metallicity-dependent in core-collapse supernova and/or being produced in double neutron star mergers with a delay time distribution greater than t−1. Furthermore, using Eu as a proxy for the radioactive r-process elements U and Th, and assuming that rocky planetary abundances reflect their parent star’s composition, we show how these elements play a key role in the evolution of the magnetic dynamo on Earth-mass planets. Specifically, we find that only above [α/H] > −0.25 do most stars’ planetary systems meet the threshold abundance of [Eu/α] < +0.06 to support a persistent magnetic dynamo, supporting the notion of a “habitable metallicity range” in the Galactic disk.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145127749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Two-stage Kick Scenario for the Peculiar Low-mass X-Ray Binary GX 1+4 特殊的低质量x射线双星GX 1+4的两阶段爆发情景

The Astrophysical Journal Letters Pub Date : 2025-09-23 DOI: 10.3847/2041-8213/ae060a

Xiangyu Ivy Wang, 翔煜王, Shi-Jie Gao and Xiang-Dong Li

{"title":"A Two-stage Kick Scenario for the Peculiar Low-mass X-Ray Binary GX 1+4","authors":"Xiangyu Ivy Wang, 翔煜王, Shi-Jie Gao and Xiang-Dong Li","doi":"10.3847/2041-8213/ae060a","DOIUrl":"https://doi.org/10.3847/2041-8213/ae060a","url":null,"abstract":"The low-mass X-ray binary (LMXB) GX 1+4 stands out with its unique properties. Despite being an old system, it hosts a strongly magnetized neutron star (NS), a trait usually linked to younger systems. Its exceptionally long orbital period (1160 days) and low eccentricity (0.101) imply that the NS formed with minimal mass loss and a weak natal kick. These features collectively point toward the NS having formed through the accretion-induced collapse (AIC) of a white dwarf. However, GX 1+4’s unusually high peculiar velocity (∼189.36 km s−1) defies standard AIC explanations. To address this discrepancy, we propose a two-stage kick scenario within the AIC framework: an initial natal kick followed by a delayed electromagnetic “rocket effect” kick. Our Monte Carlo simulations indicate that while the natal kick (≲100 km s−1) can generate a wide range of orbital eccentricities, the subsequent rocket kick (∼240–480 km s−1) explains both the high systemic velocity and low eccentricity. This two-stage kick mechanism naturally reproduces the observed characteristics of GX 1+4, provided that the NS’s initially buried magnetic field reemerges after the acceleration process ends. Our study represents the first attempt to quantitatively constrain the kick velocities in GX 1+4 and underscores the importance of possible rocket kicks in forming such peculiar LMXB systems.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145127745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of Galactic Chemical Evolution on Exoplanet Properties 星系化学演化对系外行星性质的影响

The Astrophysical Journal Letters Pub Date : 2025-09-22 DOI: 10.3847/2041-8213/ae0457

Jason H. Steffen, Cody Shakespeare, Robert Royer, David Rice and Allona Vazan

引用次数: 0

The Mid-infrared-emitting Jet in the Black Hole V404 Cygni in Quiescence 天鹅座V404黑洞中处于静止状态的中红外喷射流

The Astrophysical Journal Letters Pub Date : 2025-09-21 DOI: 10.3847/2041-8213/ae0322

E. S. Borowski, R. I. Hynes, Q. Hunt, A. J. Tetarenko, R. M. Plotkin, T. Shahbaz, P. Gandhi, T. J. Maccarone, J. C. A. Miller-Jones, C. O. Heinke, A. W. Shaw, T. D. Russell, G. R. Sivakoff, P. A. Charles, E. V. Palaiologou and P. Reig

{"title":"The Mid-infrared-emitting Jet in the Black Hole V404 Cygni in Quiescence","authors":"E. S. Borowski, R. I. Hynes, Q. Hunt, A. J. Tetarenko, R. M. Plotkin, T. Shahbaz, P. Gandhi, T. J. Maccarone, J. C. A. Miller-Jones, C. O. Heinke, A. W. Shaw, T. D. Russell, G. R. Sivakoff, P. A. Charles, E. V. Palaiologou and P. Reig","doi":"10.3847/2041-8213/ae0322","DOIUrl":"https://doi.org/10.3847/2041-8213/ae0322","url":null,"abstract":"Observations of some quiescent black hole X-ray binaries have revealed an excess of mid-infrared (MIR) emission above that expected from their donor stars. In one system, V404 Cygni, this excess has been variously suggested to arise from the accretion disk, circumbinary material, or a compact relativistic jet. Here we present simultaneous James Webb Space Telescope (JWST), Atacama Large Millimeter/submillimeter Array, and complementary multiwavelength observations undertaken to resolve this uncertainty. We observed large-amplitude 21 μm variability on short timescales with JWST, particularly a dramatic flare, which swiftly rose to ≈2.4 mJy, over 10 times the lowest observed MIR flux density. Similar variability was simultaneously observed from radio to X-ray wavelengths with other facilities throughout the campaign. This variability and the flat radio/millimeter/MIR spectral index (α = 0.04 ± 0.01) suggest that the MIR excess at and longward of 21 μm in V404 Cyg does not arise from the accretion disk or circumbinary material. Instead, the emission at 21 μm is dominated by synchrotron radiation from a jet, which persists into quiescence. This result reinforces the ubiquity of the disk–jet connection in accreting black holes across a range of masses and accretion rates.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145103603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Parallel and Perpendicular Diffusion of Energetic Particles in the Near-Sun Solar Wind Observed by Parker Solar Probe 帕克太阳探测器观测到的近日太阳风中高能粒子的平行和垂直扩散

The Astrophysical Journal Letters Pub Date : 2025-09-21 DOI: 10.3847/2041-8213/ae063f

Nibuna S. M. Subashchandar, Lingling Zhao, Andreas Shalchi, Gary Zank, Jakobus Le Roux, Hui Li, Xingyu Zhu, Ashok Silwal and Juan G. Alonso Guzman

{"title":"Parallel and Perpendicular Diffusion of Energetic Particles in the Near-Sun Solar Wind Observed by Parker Solar Probe","authors":"Nibuna S. M. Subashchandar, Lingling Zhao, Andreas Shalchi, Gary Zank, Jakobus Le Roux, Hui Li, Xingyu Zhu, Ashok Silwal and Juan G. Alonso Guzman","doi":"10.3847/2041-8213/ae063f","DOIUrl":"https://doi.org/10.3847/2041-8213/ae063f","url":null,"abstract":"We investigate energetic particle diffusion in the inner heliosphere (∼0.06–0.3 au) explored by Parker Solar Probe (PSP). Parallel (κ∥) and perpendicular (κ⊥) diffusion coefficients are calculated using second-order quasi-linear theory (SOQLT) and unified nonlinear transport theory, respectively. PSP’s in situ measurements of magnetic turbulence spectra, including sub-Alfvénic solar wind, are decomposed into parallel and perpendicular wavenumber spectra via a composite two-component turbulence model. These spectra are then used to compute κ∥ and κ⊥ across energies ranging from sub-GeV to GeV. Our results reveal a strong energy and radial distance dependence in κ∥. While κ⊥remains much smaller, it can rise accordingly in regions with relatively high turbulence levels δB/B0. To validate our results, we estimate κ∥ using an upstream time-intensity profile of a solar energetic particle event observed by the PSP and compare it with theoretical values from different diffusion models. Our results suggest that the SOQLT-calculated parallel diffusion generally shows better agreement with solar energetic particle intensity-derived estimates than the classic quasi-linear theory model. This indicates that the SOQLT framework, which incorporates resonance broadening and nonlinear corrections and does not require the introduction of an ad hoc pitch-angle cutoff, may provide a more physically motivated description of energetic particle diffusion near the Sun.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"194 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145103600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Which Solar Latitude Follows the Sunspot Cycle Exactly? 哪个太阳纬度与太阳黑子周期密切相关？

The Astrophysical Journal Letters Pub Date : 2025-09-18 DOI: 10.3847/2041-8213/ae04e3

K. P. Raju

{"title":"Which Solar Latitude Follows the Sunspot Cycle Exactly?","authors":"K. P. Raju","doi":"10.3847/2041-8213/ae04e3","DOIUrl":"https://doi.org/10.3847/2041-8213/ae04e3","url":null,"abstract":"The large-scale convection in the Sun known as supergranulation is manifested as a network structure on the solar surface. The network cells have an average lifetime of 24 hr, a size of about 30 Mm, and a lane width of about 6 Mm. We have obtained the lane widths and intensities at different latitudes from the Ca ii K spectroheliograms from the 100 yr Kodaikanal archival data. We have then calculated the cross-correlation function of lane widths and intensities with sunspot number at every latitude from 60°N to 60°S. The correlation coefficients of the quantities show an approximate north–south symmetry with broad peaks around ±(11–22)° latitude with values of about 0.8. The results imply that these latitudes follow the sunspot cycle strongly. The maximum correlation for the lane widths occurs (18 ± 2)°N and (20 ± 2)°S with no phase difference. For intensities, this happens at (13 ± 2)°N and (14 ± 2)°S with a phase difference of 1.25–1.5 yr. It is interesting to note that the lane width correlations peak during the solar maximum, whereas the intensity correlations peak 1.25–1.5 yr after the solar maximum. The results generally show that no unique latitude exactly follows the solar cycle for all quantities. The results are important in flux transport on the solar surface and have implications for the quiet Sun UV irradiance variations.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"55 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145083732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Energetic Protons in the Inner Heliosphere Exhibit Consistent ∼1 MeV Temperatures 内日球层的高能质子表现出一致的~ 1 MeV温度

The Astrophysical Journal Letters Pub Date : 2025-09-18 DOI: 10.3847/2041-8213/ae0295

H. A. Farooki, M. E. Cuesta, L. Y. Khoo, G. Livadiotis, D. J. McComas, J. S. Rankin, M. M. Shen and J. R. Szalay

{"title":"Energetic Protons in the Inner Heliosphere Exhibit Consistent ∼1 MeV Temperatures","authors":"H. A. Farooki, M. E. Cuesta, L. Y. Khoo, G. Livadiotis, D. J. McComas, J. S. Rankin, M. M. Shen and J. R. Szalay","doi":"10.3847/2041-8213/ae0295","DOIUrl":"https://doi.org/10.3847/2041-8213/ae0295","url":null,"abstract":"The solar energetic particle (SEP) proton population follows a kappa distribution distinct from the solar wind. This conclusion has been reached based on a method that tests whether there is a kappa distribution behind observed SEP power-law spectra, also estimating thermodynamic properties (density, temperature, and kappa) of the SEP population. Previously, this method was applied to a single SEP event using only measurements from IS⊙IS/HET on board the Parker Solar Probe. In this study, we applied this method to Parker Solar Probe data from 2018 to 2024. A surprising result is that despite both having small local fluctuations, the temperature is almost always close to ∼1 MeV, whereas the density spans several orders of magnitude. To validate this finding, we use an alternative method by directly fitting kappa distributions to measurements over energies ranging from 3 to 50 MeV using both LET and HET. This allows us to include energies sufficiently close to the typical temperature of ∼1 MeV. We also applied both methods to measurements from STEREO-A from 2006 to 2024. The results from both methods with both spacecraft were in agreement that the temperature of the SEP proton population is almost always close to ∼1 MeV.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"49 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145083730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Dense Dark Matter Core of the Subhalo in the Strong Lensing System JVAS B1938+666 强透镜系统JVAS B1938+666中亚晕的致密暗物质核心

The Astrophysical Journal Letters Pub Date : 2025-09-18 DOI: 10.3847/2041-8213/ae047c

Lei Lei, 磊雷, Yi-Ying Wang, 艺颖王, Qiao Li, 巧李, Jiang Dong, 江董, Ze-Fan Wang, 泽凡王, Wei-Long Lin, 炜龙林, Yi-Ping Shu, 轶平舒, Xiao-Yue Cao, 潇月曹, Da-Neng Yang, 大能杨, Yi-Zhong Fan and 一中范

{"title":"A Dense Dark Matter Core of the Subhalo in the Strong Lensing System JVAS B1938+666","authors":"Lei Lei, 磊雷, Yi-Ying Wang, 艺颖王, Qiao Li, 巧李, Jiang Dong, 江董, Ze-Fan Wang, 泽凡王, Wei-Long Lin, 炜龙林, Yi-Ping Shu, 轶平舒, Xiao-Yue Cao, 潇月曹, Da-Neng Yang, 大能杨, Yi-Zhong Fan and 一中范","doi":"10.3847/2041-8213/ae047c","DOIUrl":"https://doi.org/10.3847/2041-8213/ae047c","url":null,"abstract":"The nature of dark matter remains unknown, motivating the study of fuzzy/wave dark matter (FDM/ψDM) and self-interacting dark matter (SIDM) as alternative frameworks to address small-scale discrepancies in halo profiles inferred from observations. This study presents a nonparametric reconstruction of the mass distribution of the previously found dark subhalo in the strong lensing system JVAS B1938+666. Compared with the standard Navarro–Frenk–White profile, both SIDM and ψDM ( ) provide significantly better fits to the resulting density profile. Moreover, the SIDM model is favored over ψDM with a Bayes factor of 14.44. The reconstructed density profile features a characteristic kiloparsec-scale core (rc ≈ 0.5 kpc) with central density , exhibiting remarkable consistency with the core–halo mass scaling relations observed in Local Group dwarf spheroidals. These findings offer insights that may help address the core–cusp discrepancy in ΛCDM substructure predictions.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145083851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Gravitational Instability and Fragmentation in Collapsar Disks Supports the Formation of Subsolar Neutron Stars 坍缩星盘的引力不稳定性和碎裂支持了亚太阳中子星的形成

The Astrophysical Journal Letters Pub Date : 2025-09-17 DOI: 10.3847/2041-8213/ae045d

Yi-Xian Chen and Brian D. Metzger

{"title":"Gravitational Instability and Fragmentation in Collapsar Disks Supports the Formation of Subsolar Neutron Stars","authors":"Yi-Xian Chen and Brian D. Metzger","doi":"10.3847/2041-8213/ae045d","DOIUrl":"https://doi.org/10.3847/2041-8213/ae045d","url":null,"abstract":"We perform three-dimensional shearing box hydrodynamical simulations to explore the outcome of gravitational instability in the outer regions of neutrino-cooled disks such as those formed from the collapse of rotating massive stars (“collapsars”). We employ a physical equation of state and optically thin neutrino cooling and assume an electron fraction set by the balance of e± pair-capture reactions. Disks in a marginally stable initial state (Toomre parameter Q ≈ 1) undergo runaway cooling and fragmentation when the dimensionless cooling timescale obeys τcool ≡ tcoolΩ ≲ 10, where Ω is the orbital frequency; these conditions correspond to accretion rates ≳M⊙ s−1 on the upper end of those achieved by collapsar progenitor stars. Fragmentation leads to the formation of neutron-rich clumps (electron fraction Ye ≲ 0.1) spanning a range of masses ∼0.01–1 M⊙ around the local Jeans value. Most clumps exceed the local Chandrasekhar mass and hence will continue to collapse to nuclear densities, forming neutron stars (NSs) with subsolar masses otherwise challenging to create through ordinary stellar core collapse. Even cool disks dominated by α particles (Ye ≃ 0.5) can fragment and collapse into neutron-rich clumps capable of forming subsolar NSs. Although our simulations cannot follow this process directly, if the disk-formed NSs subsequently pair into binaries, the GW chirps from their rapid mergers are potentially detectable by ground-based observatories. The temporal coincidence of such a hierarchical NS merger chain with the collapsar gamma-ray burst and supernova would offer a uniquely spectacular multimessenger “symphony.”","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145077720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Supermassive Black Hole in a Diminutive Ultracompact Dwarf Galaxy Discovered with JWST/NIRSpec+IFU JWST/NIRSpec+IFU在一个小型超紧凑矮星系中发现了一个超大质量黑洞

The Astrophysical Journal Letters Pub Date : 2025-09-17 DOI: 10.3847/2041-8213/ae028e

Matthew A. Taylor, Behzad Tahmasebzadeh, Solveig Thompson, Eugene Vasiliev, Monica Valluri, Michael J. Drinkwater, Patrick Côté, Laura Ferrarese, Joel Roediger, Holger Baumgardt, Misty C. Bentz, Kristen Dage, Eric W. Peng, Drew Lapeer, Chengze Liu, Zach Sumners, Kaixiang Wang, Vivienne Baldassare, John P. Blakeslee, Youkyung Ko and Tyrone E. Woods

{"title":"A Supermassive Black Hole in a Diminutive Ultracompact Dwarf Galaxy Discovered with JWST/NIRSpec+IFU","authors":"Matthew A. Taylor, Behzad Tahmasebzadeh, Solveig Thompson, Eugene Vasiliev, Monica Valluri, Michael J. Drinkwater, Patrick Côté, Laura Ferrarese, Joel Roediger, Holger Baumgardt, Misty C. Bentz, Kristen Dage, Eric W. Peng, Drew Lapeer, Chengze Liu, Zach Sumners, Kaixiang Wang, Vivienne Baldassare, John P. Blakeslee, Youkyung Ko and Tyrone E. Woods","doi":"10.3847/2041-8213/ae028e","DOIUrl":"https://doi.org/10.3847/2041-8213/ae028e","url":null,"abstract":"The integral-field unit mode of the Near-Infrared Spectrograph (NIRSpec+IFU) mounted on the James Webb Space Telescope has now enabled kinematic studies of smaller and less massive compact stellar systems in which to search for central massive black holes (BHs) than ever before. We present here the first such detection using NIRSpec+IFU in its highest resolution (R ∼ 2700) mode. We report the detection of a central BH with mass = 2.1 ± 1.1 × 106M⊙ (1σ uncertainties) in UCD736 orbiting within the Virgo galaxy cluster. Schwarzschild modeling of the 1D kinematic profile rules out a zero-mass central BH at the 3σ level; however, two other independent modeling approaches fail to rule out a zero-mass BH at >1σ significance. The presence of such a massive BH strongly argues against a globular cluster origin of this ultracompact dwarf galaxy (UCD), and rather suggests a tidally stripped formation route from a former ≳109M⊙ dwarf galaxy host. This represents the detection of a BH in the most compact (rh ≈ 15 pc) stellar system to date, with a corresponding to ∼8% of the system’s stellar mass, roughly in line with previously reported UCD BH detections and comparable to the BH detected in the compact elliptical galaxy NGC4486B.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145077715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0